Organized crime behavior of shell-company networks in procurement: prevention insights for policy and reform

In recent years, the analysis of economic crime and corruption in procurement has benefited from integrative studies that acknowledge the interconnected nature of the procurement ecosystem. Following this line of research, we present a networks approach for the analysis of shell-companies operations in procurement that makes use of contracting and ownership data under one framework to gain knowledge about the organized crime behavior that emerges in this setting. In this approach, ownership and management data are used to identify connected components in shell-company networks that, together with the contracting data, allows to develop an alternative representation of the traditional buyer-supplier network: the module-component bipartite network, where the modules are groups of buyers and the connected components are groups of suppliers. This is applied to two documented cases of procurement corruption in Mexico characterized by the involvement of large groups of shell-companies in the misappropriation of millions of dollars across many sectors. We quantify the economic impact of single versus connected shell-companies operations. In addition, we incorporate metrics for the diversity of operations and favoritism levels. This paper builds into the quantitative organized crime in the private sector studies and contributes by proposing a networks approach for preventing fraud and understanding the need for legal reforms.Comment: Corruption; fraud; public procurement; shell-companies; ownership; organized crime; network analysi

Diffusion limited aggregation, resetting and large deviations of Brownian motion

Models of fractal growth commonly consider particles diffusing in a medium and that stick irreversibly to the forming aggregate when making contact for the first time. As shown by the well-known diffusion limited aggregation (DLA) model and its generalisations, the fractal dimension is sensitive to the nature of the stochastic motion of the particles. Here, we study the structures formed by finite-lived Brownian particles, i.e., particles constrained to find the aggregate within a prescribed time, and which are removed otherwise. This motion can be modelled by diffusion with stochastic resetting, a class of processes which has been widely studied in recent years. In the short lifetime limit, a very small fraction of the particles manage to reach the aggregate. Hence, growth is controlled by atypical Brownian trajectories, that move nearly in straight line according to a large deviation principle. In $d$ dimensions, the resulting fractal dimension of the aggregate decreases from the DLA value and tends to 1, instead of increasing to $d$ as expected from ballistic aggregation. In the zero lifetime limit one recovers the non-trivial model of "aggregation by the tips" proposed long ago by R. Jullien [J. Phys. A: Math. Gen. 19, 2129 (1986)].Comment: 13 pages, 5 figure

Cognitive rigor: blending the strengths of Bloom's taxonomy and Webb's depth of knowledge to enhance classroom-level processes

To teach the rigorous skills and knowledge students need to succeed in future college entry courses and workforce training programs, education stakeholders have increasingly called for more rigorous curricula, instruction, and assessments. Identifying the critical attributes of rigor and measuring its appearance in curricular materials is therefore fundamental to progress in this area. By superposing two widely accepted models for describing rigor — Bloom's Taxonomy of Educational Objectives and Webb’s Depth-of Knowledge (DOK) model — this article defines cognitive rigor (CR) and introduces the CR matrix for analyzing instruction and enhancing teacher lesson planning. Two large-scale collections of student work samples analyzed using the CR matrix are presented, illustrating the preponderance of curricular items aligned to each cell in the matrix. Educators should use the cognitive rigor matrix to align the content in their curricular materials to the instructional techniques used in classroom delivery.Vice President for Researc

Mississippi State University Libraries Strategic Plan 2024-2028: Full Version

This document serves as the 2024-2028 Strategic Plan for the Mississippi State University Libraries

Mississippi State University Libraries Strategic Plan 2024-2028: Public Version

This document serves as the 2024-2028 Strategic Plan for the Mississippi State University Libraries. This version is summarized and arranged for public consumption

Is there a relationship between the overhead press and split jerk maximum performance? Influence of sex

The aims of this study were to (I) determine the differences and relationship between the overhead press and split jerk performance in athletes involved in weightlifting training, and (II) explore the magnitude of these differences in one-repetition maximum (1RM) performances between sexes. Sixty-one men (age: 30.4 ± 6.7 years; height: 1.8 ± 0.5 m; body mass 82.5 ± 8.5 kg; weightlifting training experience: 3.7 ± 3.5 yrs) and 21 women (age: 29.5 ± 5.2 yrs; height: 1.7 ± 0.5 m; body mass: 62.6 ± 5.7 kg; weightlifting training experience: 3.0 ± 1.5 yrs) participated. The 1RM performance of the overhead press and split jerk were assessed for all participants, with the overhead press assessed on two occasions to determine between-session reliability. The intraclass correlation coefficients (ICC) and 95% confidence intervals showed a high reliability for the overhead press ICC = 0.98 (0.97 – 0.99). A very strong correlation and significant differences were found between the overhead press and split jerk 1RM performances for all participants (r = 0.90 [0.93 – 0.85], 60.2 ± 18.3 kg, 95.7 ± 29.3 kg, p ≤ 0.001). Men demonstrated stronger correlations between the overhead press and split jerk 1RM performances (r = 0.83 [0.73-0.90], p ≤ 0.001) compared with women (r = 0.56 [0.17-0.80], p = 0.008). These results provide evidence that 1RM performance of the overhead press and split jerk performance are highly related, highlighting the importance of upper-limb strength in the split jerk maximum performance

Comparing the effectiveness of a short-term vertical jump vs. weightlifting program on athletic power development

Efficient training of neuromuscular power and the translation of this power to sport-specific tasks is a key objective in the preparation of athletes involved in team-based sports. The purpose of the current study was to compare changes in center of mass (COM) neuromuscular power and performance of sport-specific tasks following short-term (6-week) training adopting either Olympic Style Weightlifting (WL) exercises or vertical jump (VJ) exercises. Twenty six recreationally active males (18-30 years; height: 178.7±8.3 cm; mass: 78.6±12.2 kg) were randomly allocated to either a WL or VJ training group and performance during the countermovement jump (CMJ), squat jump (SJ), depth jump (DJ), 20m sprint and the 5-0-5 agility test assessed pre- and post-training. Despite the WL group demonstrating larger increases in peak power output during the CMJ (WL group: 10% increase, d=0.701; VJ group: 5.78% increase, d=0.328) and SJ (WL group: 12.73% increase, d=0.854; VJ group: 7.27% increase, d=0.382), no significant between-group differences were observed in any outcome measure studied. There was a significant main effect of time observed for the three vertical jumps (CMJ, SJ, DJ), 0-5m and 0-20m sprint times, and the 5-0-5 agility test time, which were all shown to improve following the training (all main effects of time p<0.01). Irrespective of the training approach adopted by coaches or athletes, addition of either WL or VJ training for development of power can improve performance in tasks associated with team-based sports, even in athletes with limited pre-season training periods